This invention relates to the simultaneous preparation of an aromatic acid chloride and an aliphatic carboxylic acid chloride.
The compounds prepared by the method of this invention are well known chemical intermediates used in the preparation of dyes, pharmaceuticals, lubricants, and polymers. Since their use has become widespread, several various methods have been developed to produce these compounds.
Generally, the aromatic acid chlorides have been more widely used and most of the prior art development has been directed to the production of aromatic acid chlorides. In spite of this attention, the methods that have been developed all suffer from various disadvantages which have plagued the production of aromatic acid chlorides until the present invention was made.
The prior art methods for preparing aromatic acid chlorides are typified by the following:
1. The reaction of an aromatic acid with thionyl chloride or phosphorus pentachloride
2. The reaction of benzaldehyde with chlorine, Chem Abstr 82,1975 155697 Netherlands patent application Ser. No. 73 06,212.
3. The reaction of .alpha.,.alpha..alpha.-benzotrichlorides with water or benzoic acids in the presence of an acid catalyst. Japan Kokai No. 74, 132,028, Chem Abstr 82,1975 139750; U.S. Pat. Nos. 1,793,917; 2,016,784; 3,835,187.
4. The reaction of .alpha.,.alpha.,.alpha.-trichlorotoluenes with sulfur dioxide, U.S. Pat. Nos. 3,775,476 and 3,806,545; Chem Abstr. 80 26973w.
The first three methods described above, all suffer from the common disadvantage of producing stoichiometric amounts of hydrogen chloride as an unwanted byproduct which must be neutralized or destroyed in some other way. The fourth method requires the use of high pressure to effect reaction.
Therefore, it is a principle object of this invention to provide a process for producing an aromatic acid chloride without producing any undesirable products.
Another object of the present invention is to provide a process embodying the features characterized above which is capable of being conducted at ambient conditions, thereby eliminating the need for elevated pressure.
Another object of the present invention is to provide a process embodying the feature characterized above wherein an additional commercially desirable product is also produced.
A further object of the present invention is to provide a process embodying the features characterized above wherein the products are easily separated in a substantially pure form directly during the process, thereby eliminating any costly purification.
Another object of the present invention is to provide a process which is easily and inexpensively performed.
Other objects of the invention will in part be obvious and will in part appear hereinafter.